The fatty acid alkyl ester sulfonate metal salt is also referred to as α-sulfo fatty acid alkyl ester salt or α-SF salt, which is mainly used as the material for granular detergents for clothes (WO2004/111166). The methyl ester salt (MES) is most widely used as the material for granular detergents.
To produce the granular detergent, for example, the α-SF salt in a slurry form is concentrated to obtain a solid, and then the solid is ground into powders. Those powders are dry-blended with other surfactants, builders and the like, thereby producing the granular detergent. When the α-SF salt is transported to the place for dry-blending, the α-SF salt in a solid form such as flakes or pellets is more convenient than the salt in a liquid form such as a paste or concentrate.
However, the solid products may cause agglomeration to form cakes under the circumstances of heavy load or high temperatures during the transportation. This will hinder the process subsequent to the transportation and worsen the handling properties.
Accordingly, it is necessary to prevent the solid matters of α-SF salt from consolidating with each other and forming cakes.